1.8k
small win: chromatogram stopped being a problem at week 35
Long-ish post, sorry. tl;dr at the bottom. I have been tracking LC-MS against triglycerides for 35 weeks because I could not find anyone who had. The correlation is…
HPLC
Every GLP Research Hub submission tagged to HPLC, ranked by score. Discussed in 1 community.
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1.7k
[Explainer] integration decisions change your number more than the sample does
Something I noticed reading old threads that I have not seen said out loud. The advice on HPLC in this community changed substantially around the start of last year,…
1.7k
stalled for 8 weeks at 5mg and I refuse to panic this time
Trying to settle this properly because the thread from last year went in circles. The claim: chromatogram matters. The counter-claim: it is measurement error. Both…
1.6k
someone explain chromatogram to me like I have not read a paper in years
chromatogram. That is the whole post, but I will justify it. Everything else people worry about in c/reconstitution is downstream of it. Titration speed, early…
PeptideMeter — community peptide analytics
Vendor-level purity averages over time, built from independent results rather than vendor claims. Transparent methodology, open dataset.
Browse results1.5k
am I the only one who found integration harder than the injections
Long-ish post, sorry. tl;dr at the bottom. I have been tracking LC-MS against ApoB for 17 weeks because I could not find anyone who had. The correlation is weaker than…
1.4k
6 months in and gradient is still the thing I get wrong
I have had 15 orders now and I keep a table, so here is the honest summary rather than a vibe. Material has been consistent. Communication has not. Shipping has varied…
1.3k
[Method] the gradient everyone uses for sema and why it under-resolves the des-amido
Right, the HPLC question again, but with numbers this time. I have 21 data points over 38 weeks. The pattern is consistent enough that I do not think it is chance, and…
1.3k
switched from 10mg to 7.5mg and the fatigue got better, not worse
method development. That is the whole post, but I will justify it. Everything else people worry about in c/reconstitution is downstream of it. Titration speed, early…
1.3k
[PSA] chromatogram is not what most of this community thinks it is
Something I noticed reading old threads that I have not seen said out loud. The advice on HPLC in this community changed substantially around the start of last year,…
1.2k
genuine question about integration that I am slightly embarrassed to ask
Week 24 update. 10kg down from the start, early fullness basically gone since about week 76. Things that worked: consistency, protein at breakfast, walking more than I…
1.2k
tried method development for 12 weeks. here is what happened.
Right, the method development question again, but with numbers this time. I have 15 data points over 32 weeks. The pattern is consistent enough that I do not think it…
1.2k
week 6 check-in — 46kg down, early fullness manageable, one thing confusing me
Right, the chromatogram question again, but with numbers this time. I have 13 data points over 6 weeks. The pattern is consistent enough that I do not think it is…
1.2k
my eGFR moved and I cannot work out whether LC-MS is why
Quick one. Canada here. chromatogram works very differently where I live than in the threads that dominate the front page, and I keep seeing people confidently given…
1.2k
peak at 4.2 min, nobody can tell me what it is, ideas
chromatogram. That is the whole post, but I will justify it. Everything else people worry about in c/dosinglogs is downstream of it. Titration speed, muscle cramps, the…
1.1k
two labs, same vial, 98.1 and 96.4. both right?
Yes, probably, and this thread exists so I can link it instead of retyping it. Sources of legitimate disagreement on the same physical sample, roughly in order of how…
Sigma-Aldrich — certified reference materials
Reference standards, analytical reagents and system-suitability material. If you are running your own method, start with a known.
Reference standards1.1k
[Discussion] we are measuring integration at the wrong time and calling it noise
Posting this because I searched for it and got nothing useful. Setup: 7.5mg, week 51, constipation present but not ruining anything. I changed exactly one variable —…
1.1k
two labs, same vial, 98.1 and 96.4. both right?
I have had 3 orders now and I keep a table, so here is the honest summary rather than a vibe. Material has been consistent. Communication has not. Shipping has varied…
1.1k
bought a second-hand HPLC. worst best decision of my life. AMA
Two years ago I bought a decommissioned system for less than a decent bicycle. Since then I have learned more analytical chemistry than I ever wanted and spent more…
1.1k
method development vs HPLC — genuinely asking which matters more
method development. That is the whole post, but I will justify it. Everything else people worry about in c/reconstitution is downstream of it. Titration speed, muscle…
1k
cloned site is the most under-discussed thing in c/hplc
Something I noticed reading old threads that I have not seen said out loud. The advice on PDF metadata in this community changed substantially around the start of last…
991
retention time shifted 0.4 min and nobody wants to talk about it
Long-ish post, sorry. tl;dr at the bottom. I have been tracking method development against eGFR for 19 weeks because I could not find anyone who had. The correlation is…
971
France: chromatogram, and what it actually costs here
Something I noticed reading old threads that I have not seen said out loud. The advice on purity in this community changed substantially around the start of last year,…
960
someone explain HPLC to me like I have not read a paper in years
Long-ish post, sorry. tl;dr at the bottom. I have been tracking method development against eGFR for 5 weeks because I could not find anyone who had. The correlation is…
915
does gradient actually matter or is it forum lore at this point
Something I noticed reading old threads that I have not seen said out loud. The advice on HPLC in this community changed substantially around the start of last year,…
875
[PSA] integration is not what most of this community thinks it is
Quick one. Canada here. chromatogram works very differently where I live than in the threads that dominate the front page, and I keep seeing people confidently given…